Acoustical instrument.



L. LUMIERE' COUSTICAI. INSTRUMENT. APPumon man wu s. 1912.

1,253,61 3. Patented Jan. 15,1918.v

UNITED sTATEs PATENT oEErcE.

. l LOUIS LUMIERE,v OF LYON, FRANCE, ASSIGNOB TO VICTOR TALKING MACHINE OOM- PANY,

A CORPORATION F NEW JERSEY.

ACUSTICAL INSTRUMENT.

4'Specification of Letters atent.

VPatented J an. 15, 1918.

Application led July 5,1912. Serial No. 707,789.

To all whom it 'may concern:

Be it known that I, Louis LUMIERE, a citizen of the Republic of France, residing at Lyon, in the Republic of France, have invented certain new and useful Improvements in Acoustical Instruments, of which the following Yis a specification.

The main objects of this invention are, to provide an improved sound box for talking machines; to provide in a sound box for talking machines an improved diaphragm and mounting therefor; `and to provide other improvements as will appear hereinafter.

' therewith for i flat and parallel marginal retaining In the accompanying drawings, Figure 1 is a fragmentary front elevation of a sound box constructed in accordance with this invention andapplied in a talking machine; Fig. 2 a side elevation of the same partly in longitudinal central section; and Fig. 3 a transverse section of the same on line 3-3 of Fig. 1, looking in the direction of the-arrows.

Referring to the drawings, one embodiment of this invention comprises a sound box including a casing 1, a substantially rectangular and preferably substantially square flexible diaphragm 2, and a' stylus bar 3 mounted to oscillate upon the casing and connected to the diaphragm 2.

The casing 1 includes a substantially flat rigid back plate 5, preferably made of brass or other similar material, and. preferably rectangular elevation. This back plate is provided centrally with a cylindrical aperture 6, which is surrounded upon the rear side of the back plate by a yielding tubular extension 7 which is clamped to the back plate by means of headed screws 8 which are threaded into the back plate through apertures 9 provided therefor in the yielding extension. The yielding tubular extension 7 is provided with an internal rigid tubular bushing or lining 10 having a pin 11 projecting inward y therefrom and rigidly connected holding the sound box in place upon a tubular support 12..

For holding the diaphragm 2 1n position, the back plate 5 is provided with forwardly projecting oppositely disposed substantially walls 15 and 16 integral with or rigidly secured to the back 5. The front edge of each and substantially square in front of these retaining walls 15 and 16 is pr0 vided withan inwardly extendin flat flange 17 integral therewith or ri'gidgly secured thereto, and arranged in a plane parallel to the back plate 5. ln the recess formed .by the back plate and each retaining wall 15 and 16 and its flange 17 are two spaced yielding supports 20, one of these supports being outside of and spaced from the other support, the vouter support being in contact with and normally compressed by the corresponding flange 17, and the inner support fitting snugly and being slightly conipressed in an internal recess 21 provided therefor in the front face of the back plate 5.

The diaphragm 2 is spaced slightly in front ofthe back. plate 5 and is arranged to be normally parallel thereto, two opposite edges or marginal portions of the diaphragm projecting between the correspondin tubular supports 20 respectively and eing yieldingly clamped in position thereby, these edges of the diaphragm being spaced from the retaining walls 15 and 16 to permit of the movement of the diaphragm in its own plane. The other two parallel edges or marginal portions 25 of the diaphragm are substantially flush with the corresponding edges of the back plate 5 and are free Ato flex throughout their full lengths with respect to the back plate.

To prevent the escape of sound waves between the free edges of the diaphra m and the back plate 5, a strip 26 of very t in and flexible material, such as cloth or woven fabric, or any other suitable yielding material, is secured to each free marginal portion or edge 25 of the diaphragm and the adjacent end wall 27 of the back plate 5 so as to form a yielding closure for the space between the edge 25 of the diaphragm and the opposite edge of the back plate 5. Each strip 26 is preferably arranged to project over the front face of the diaphragm 2 and may be secured in position against the front face of the diaphragm by means of a coating 28 of glue or cement or other similar material, applied between the diaphragm and the strip, and the strip may be also secured to the diaphragm by means 'of stitching 29. A coating 3Q of cement er glue may also be applied between each strip and the adjacent end wall iii' of the back plate 5 to secure the strip to the bacia plate..

Between the diaphragm andfthe back plate, each strip 26 is norinally folded inwardly, as at 31, to permit of the free movement of the corresponding edge of thediaphragm.

For flexing the diaphragm-2 substantially uniformly throughout its full width, the diaphragm is provided with a substantially rigid Aflat bridge. or rib 35 projecti g upwardly therefrom in a piane perpen'icu ar thereto, and arranged substantially midway between and parallel to the edges of the diaphragm yieldingly restrained by the yielding supports 20. 'This bridge is preferably made of very thin' steel and is vprovided on its inner edge with a dat, narrow flange 36 which is secured to the diaphragm by meansv of rivets 37 extending through the flange andthe diaphragm. A coating 38 of cement may be applied between the flange and the diaphragm. The bridge preferably tapers in width from its central portion outwardly in opposite directions, and the outer edge of the bridge is preferably' curved from end to end, the bridge preferably extending the greater part of the ull width of the diaphragm.

The stylus bar 3 preferably comprises a yvery thin flat portion 40 made preferably of ksteel and arranged in a plane perpendicular to the diaphragm 2 and substantially perpendicular to the bridge 35. This portion of the stylus bar tapers in width inwardly towardthe bridge 35 and is reduced in width adjacent to its inner end to a Very small di- 'mensiom as at 41, opposite the bridge, to permit the bar to flex readily at this point. lust inside of this reduced portion, the xstylus bar is slightly enlarged, as at 42, and this enlarged portion is connected to the lbridge 35 and to the diaphragm 2 by means of ametallic strip 43. The outer end of this strip 43 is bifurcated, embraces and is securedto the enlarged end 42 of the stylus bar by means ofsolder, orin any other suitable manner, and the strip bears against the upper side of the bridge 35 and is secured thereto by solder or otherwise. The inner end ofthe strip is preferably flanged and is Secured tothe flanged portion of the bridge fb'y means of a'headed screw 44 extending through the diaphragm and the .flanged portion of thev bridge and threaded in the anged portion of the strip. :For mounting the stylus bar 3 to oscillate with respect to the casing 1 upon a fixed axis 'parallel to the plane `of 'thediaphraglm and parallel to the retaininglwalls'15, the outer 'portion of the stylus -bar is enlarged to form oppositely disposed and comparatively thick and rigid extenslons 50- -prov'ided on vtheir inner surfaces with spaced V-shaped grooves 51 in which engage knife edges 52 projecting ri idly outwardly from a rigid base plate'5 rigidly secured to the corresponding retainingiwall 15 -of-thesound box casing. The extensions 50 are held in engagement with the knife edges 52 by means of a pair of o positely disposed springs 54, one

end of eac spring being connected.- to one of the extensions, and the'other end of each spring being adjustably connected yto the base plate 5 by means of a headed screw 55 extendin through the spring and threaded into the ase plate 53 and carrying a lock nut 56'threade, thereon between the spring and the'base plate. The outer end of the stylus bar 3 is provided with the usual socket57 adapted'togreceive a stylus 58, and vwith a set 'screw 59 arranged to hold lthe stylus in a plane.

This improved sound box is adapted to coperate with the usual sound record 60, having lateral undulations corresponding to sound waves or any other suitable record, mounted upon a rotary record support 61. When the .sound box is used in Connection with a disk-record, as shown, the sound box is preferably arranged so vthat its diaphragm 2 will be in a plane perpendicular to the plane of the record, and so that the stylus and stylus bar will incline, as usual, with res ect to the record.

n this instance. the tubular support 12,

which vcarries the sound box,l is pivotally connected to the free end of a hollow tone arm 62 with which it communicates, and whchis mounted to swing in a plane parallel to the record. lt is to be understood, of course, that the sound box may also be used with cylindrical records, or with records of vany suitable shape, also that the stylus bar and its mounting may be modited, if necessary, to adapt the sound box for use with any particular record.

In the operation of this improved sound box, it is evident that the diaphragm flexes freely between the two pairs of spaced tubular supports in response to the oscillatien of the stylus bar. the restrained edges of the diaphragm consequently alternately approaching and receding from each other.

Although only a single form has been illustrated in which this invention may be embodied, the invention is not limited to the specific construction shown, but may be embodied in various other forms to meet various requirements, without departing from the spirit of this invention or the scope of the appended claims.

Having thus fully described vthis inven tion, I claim and desire to protect'by Letters Patent ofthe United States:

1. In a sound boX, the combination :with a flexible substantially rectangular diaphragrn, provided with means substantially midway between two of the opposite sides of said diaphragm and extending transversely thereof and secured thereto for holding the longitudinally central portion of said diaphragm against flexing transversely,

- comprising an and means connected to said rst mentioned means for flexing said diaphragm longitudinally.

2. In a sound box, the combination with a flexible substantially rectangular diaphragm, of means engaging opposite-mar- 'nal portions of said diaphragm for holding said diaphragm in position, and elongated means uniformly secured to said diaphragm intermediate" of said ortions and parallel thereto for flexing sai diaphragm. 3. In a sound a polygonal diaphragm, of a pair of substantially straight yielding supports parallel with and adjacent to each of a pair of opposite sides, and engaging respectively the opposite sides of said diaphragm, said edges being yieldinglyrestrained by said supports, freely 'movable closures connecting the intermediate edges of said diaphragm to the sound box casing, and means connected to said diaphragm parallel to said restrained edges and intermediateof said supports for flexing said diaphragm on lines at right angles to said restrained edges, said means elongated reinforced member and being operative to restrain said diaphragm from being flexed on lines parallel to said restrained edges.

4. In a sound box, the combination with a polygonal diaphragm, of a pair of substantially straight yielding supports parallel with and adjacent to each of a pair of opposite edges and engaging the respective opposite sides of said diaphragm, said edges being yieldingly restrained by said supports,

freely movable closures connecting the intermediate edges of said diaphragm to the sound box casing, and means connected to said diaphragm intermediate of said supports for flexing the same at right an les to said supports and for preventing the exure of said diaphragm on lines parallel to said supports, said means comprisin an elongated reinforced member exten ing transversely of s'aid diaphragm and uniformly engaging therewith.

5. In an acoustical instrument, a polygonal diaphragm having opposite yieldingly restrained edges and opposite Afree edges, and a folded yielding member secured to eacb of said last-named edges.

In an acoustical instrument, a flexible polygonal diaphragm having free edges, and a plaited yielding member secured to each of said last-named edges.

7 In a sound box, the combination of a casing with a diaphragm, means restraining opposite edges -of saidV diaphragm, and freely movable closures comprising a fold connecting said diaphragm to said casing iny termediate of said edges.

8. In a. sound box, the combination with Aa exible diaphragm, of means restraining a flexible diaphragm,

box, the combination with 'parallel to said means,

to oscillate about an axis substan-l to iex at all points between oppositev yieldingly restrained edges "and oppositey said diaphragm at spaced points and means engaging said diaphragm between said points and arranged to flex said diaphragm on a line connecting said points and to hold said diaphragm against flexing on a line perpendicular to said first mentioned line.

9. In a sound box, the combination with of means restraining spaced portions of said diaphragm, an elongated substantially rigid rib secured to said diaphragm and spaced between said portions and extending transversely with respect to a line connecting said portions, and'means coperating with vsaid rib to Hex said diaphragm in accordance with sound waves, said rib being maintained at all ,times in parallelism with a given straight line and said diaphragm being free points between said rib and each of said portions, said rib being operative to prevent to Hex at allpendicular to said first mentioned line.

10. .In a sound box, the combination with a substantially rectangular flexible diaphragm. of spaced substantially parallel means restraining opposite marginal portions of said diaphragm, a comparatively rigid rib spaced between and parallel to said marginal portions and secured to said diaphragm, and a stylus bar connected to said rib and mounted to oscillate about an .axis arallel thereto for exin said diaphragm, said diaphragm being ree to flex at all points between said rib and each of said marginal portions and restrained from' flexure on lines parallel to said parallel means.

11. In a sound box the combination with a iexible diaphragm, of substantially parallel means restraining oppositely disposed marginal portions of said diaphragm, -an elongated substantially rigid rib engagin said diaphragm between said portions an and a stylus bar mounted tially parallel to said rib and arranged to vibrate said rib, said diaphragm being free said rib and each of said marginal portions 12. A sound bxcomprising a flexible diaphragm having two substantiall parallel diametrcally opposite margina edges., yielding means carried by said casing and restraining said edges, an elongated rib substantially parallel to said edges and to said yielding means, and engaging said diaphragm, and a stylus bar connected to said rib and arranged to oscillate about an axis substantially parallel thereto, said diaphragm being free to flex at every point between said rib and'said yielding means per,- pendicular to said restrained edges.

13. A sound box comprising a casing, a flexible diaphragm having two substantially parallel diametrically opposite marginal edges, yielding means carried by said casing casing, a

and restraining said edges, an elongated rib substantially parallel to said edges and engaging said diaphragm, and extending the Correction in Letters Patent No. l

greater part of the distance between opposite edges of said diaphragm, and a stylus bar connected to said rib and arranged to oscillate about an axis substantially parallel thereto, said vdiaphragm being free to dex at every point between said rib and said yielding means.

14, A sound box comprising a flexible diaphragm, of substantially uniform thickness, means comprising a plurality of straight tubular gaskets restraining opposite marginal portions of said diaphragm, an elongated comparatively rigid element secured to said diaphragm between said portions and extending the greater portion of the distance between opposite marginal edges of 'said diaphragm and substantially parallel to said i restrained edges, and'means arranged to vibrate said element in accordance with sound waves, said diaphragm being free to Hex at every point between said element and said restraining means along lines at right angles to said restrained marginal portions, said rib serving to yrestrain said diaphragm from flexure along lines at right angles to the free` marginal portions thereof. l5. In a sound box, the combination of a C1. isi-31.v

1918, upon the application' of Louis Lumiere', of Lyon, France,

-ing correction'as follows: Pages, line 53, read parallel; and that the said Letters Patent should-be` read with therein that the same may conform to the record of the case Signed and seal-ed this 5th day of MarchfA. 1).,1 1918.

diaphragm free at opposite edges'and restrained adjacent opposite edges 'perpendicular to said first mentioned edges, and means for preventing flexure of" said diaphragm except on lines substantially at right angles to said restrained edges.

16. In a sound box, the combination of a rectangular diaphragm restrained adjacent one pair of oppositely disposed edges only, and means extending substantially across the face of said diaphragm operative to prevent the Hexure of said diaphragm on lines parallel to said restrained edges.

17. In a sound box, the combination of a square diaphragm, said diaphragmalong lines parallel to and adjacent one pair of its oppositly disposed edges, and means secured to and extending substantially across the face of the diaphragm operative to flex said diaphragm along lines at right angles to said first inentioned means and to prevent 'lexure thereof along lines perpendicular thereto.

In witness whereof, I have hereunto set my hand this 14th day of June, A. D., 1912.

LOUIS LUMIERE.

It is hereby certied that in Letters Patent No. 1,253,613, granted January- 15,

for an improvement e in l"Acoustical Instruments, an error appearsv in theprinted specification requirclaim 17, for the` word perpendicular this correctiiin l' in the Patent Olice.

. R. F. WHITEHEAD,

Acting Commissioner of Patents. 

